Fix T41414, T41386.
[blender.git] / source / blender / editors / sculpt_paint / paint_image_proj.c
1 /*
2  * ***** BEGIN GPL LICENSE BLOCK *****
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16  *
17  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
18  * All rights reserved.
19  *
20  * The Original Code is: some of this file.
21  *
22  * Contributor(s): Jens Ole Wund (bjornmose), Campbell Barton (ideasman42)
23  *
24  * ***** END GPL LICENSE BLOCK *****
25  */
26
27 /** \file blender/editors/sculpt_paint/paint_image_proj.c
28  *  \ingroup edsculpt
29  *  \brief Functions to paint images in 2D and 3D.
30  */
31
32 #include <float.h>
33 #include <string.h>
34 #include <stdio.h>
35 #include <math.h>
36
37 #include "MEM_guardedalloc.h"
38
39 #ifdef WIN32
40 #  include "BLI_winstuff.h"
41 #endif
42
43 #include "BLI_blenlib.h"
44 #include "BLI_linklist.h"
45 #include "BLI_math.h"
46 #include "BLI_math_color_blend.h"
47 #include "BLI_memarena.h"
48 #include "BLI_threads.h"
49 #include "BLI_utildefines.h"
50
51 #include "BLF_translation.h"
52
53 #include "PIL_time.h"
54
55 #include "IMB_imbuf.h"
56 #include "IMB_imbuf_types.h"
57
58 #include "DNA_brush_types.h"
59 #include "DNA_material_types.h"
60 #include "DNA_mesh_types.h"
61 #include "DNA_node_types.h"
62 #include "DNA_object_types.h"
63
64 #include "BKE_camera.h"
65 #include "BKE_colortools.h"
66 #include "BKE_context.h"
67 #include "BKE_depsgraph.h"
68 #include "BKE_DerivedMesh.h"
69 #include "BKE_idprop.h"
70 #include "BKE_brush.h"
71 #include "BKE_image.h"
72 #include "BKE_library.h"
73 #include "BKE_main.h"
74 #include "BKE_material.h"
75 #include "BKE_mesh.h"
76 #include "BKE_mesh_mapping.h"
77 #include "BKE_paint.h"
78 #include "BKE_report.h"
79 #include "BKE_scene.h"
80 #include "BKE_texture.h"
81
82 #include "UI_view2d.h"
83 #include "UI_interface.h"
84
85 #include "ED_paint.h"
86 #include "ED_screen.h"
87 #include "ED_uvedit.h"
88 #include "ED_view3d.h"
89
90 #include "GPU_extensions.h"
91
92 #include "WM_api.h"
93 #include "WM_types.h"
94
95 #include "RNA_access.h"
96 #include "RNA_define.h"
97 #include "RNA_enum_types.h"
98
99 #include "GPU_draw.h"
100
101 #include "IMB_colormanagement.h"
102
103 #include "paint_intern.h"
104
105 /* Defines and Structs */
106 /* FTOCHAR as inline function */
107 BLI_INLINE unsigned char f_to_char(const float val)
108 {
109         return FTOCHAR(val);
110 }
111
112 /* ProjectionPaint defines */
113
114 /* approx the number of buckets to have under the brush,
115  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
116  *
117  * When 3 - a brush should have ~9 buckets under it at once
118  * ...this helps for threading while painting as well as
119  * avoiding initializing pixels that wont touch the brush */
120 #define PROJ_BUCKET_BRUSH_DIV 4
121
122 #define PROJ_BUCKET_RECT_MIN 4
123 #define PROJ_BUCKET_RECT_MAX 256
124
125 #define PROJ_BOUNDBOX_DIV 8
126 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
127
128 //#define PROJ_DEBUG_PAINT 1
129 //#define PROJ_DEBUG_NOSEAMBLEED 1
130 //#define PROJ_DEBUG_PRINT_CLIP 1
131 #define PROJ_DEBUG_WINCLIP 1
132
133 /* projectFaceSeamFlags options */
134 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
135 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
136 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
137 #define PROJ_FACE_SEAM2 (1 << 1)
138 #define PROJ_FACE_SEAM3 (1 << 2)
139 #define PROJ_FACE_SEAM4 (1 << 3)
140
141 #define PROJ_FACE_NOSEAM1   (1 << 4)
142 #define PROJ_FACE_NOSEAM2   (1 << 5)
143 #define PROJ_FACE_NOSEAM3   (1 << 6)
144 #define PROJ_FACE_NOSEAM4   (1 << 7)
145
146 /* face winding */
147 #define PROJ_FACE_WINDING_INIT 1
148 #define PROJ_FACE_WINDING_CW 2
149
150 #define PROJ_SRC_VIEW       1
151 #define PROJ_SRC_IMAGE_CAM  2
152 #define PROJ_SRC_IMAGE_VIEW 3
153 #define PROJ_SRC_VIEW_FILL  4
154
155 #define PROJ_VIEW_DATA_ID "view_data"
156 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
157
158
159 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
160  * as this number approaches  1.0f the likelihood increases of float precision errors where
161  * it is occluded by an adjacent face */
162 #define PROJ_FACE_SCALE_SEAM    0.99f
163
164 #define PROJ_BUCKET_NULL        0
165 #define PROJ_BUCKET_INIT        (1 << 0)
166 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
167
168 /* used for testing doubles, if a point is on a line etc */
169 #define PROJ_GEOM_TOLERANCE 0.00075f
170 #define PROJ_PIXEL_TOLERANCE 0.01f
171
172 /* vert flags */
173 #define PROJ_VERT_CULL 1
174
175 /* to avoid locking in tile initialization */
176 #define TILE_PENDING SET_INT_IN_POINTER(-1)
177
178 /* This is mainly a convenience struct used so we can keep an array of images we use
179  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
180  * because 'partRedrawRect' and 'touch' values would not be thread safe */
181 typedef struct ProjPaintImage {
182         Image *ima;
183         ImBuf *ibuf;
184         ImagePaintPartialRedraw *partRedrawRect;
185         volatile void **undoRect; /* only used to build undo tiles during painting */
186         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
187                           * Here we store the mask rectangle */
188         bool **valid; /* store flag to enforce validation of undo rectangle */
189         int touch;
190 } ProjPaintImage;
191
192 /* Main projection painting struct passed to all projection painting functions */
193 typedef struct ProjPaintState {
194         View3D *v3d;
195         RegionView3D *rv3d;
196         ARegion *ar;
197         Scene *scene;
198         int source; /* PROJ_SRC_**** */
199
200         /* the paint color. It can change depending of inverted mode or not */
201         float paint_color[3];
202         float paint_color_linear[3];
203
204         Brush *brush;
205         short tool, blend, mode;
206         int orig_brush_size;
207         float brush_size;
208         Object *ob;
209         /* end similarities with ImagePaintState */
210
211         DerivedMesh    *dm;
212         int dm_totface;
213         int dm_totvert;
214         int dm_release;
215
216         MVert          *dm_mvert;
217         MFace          *dm_mface;
218         MTFace         **dm_mtface;
219         MTFace         **dm_mtface_clone;    /* other UV map, use for cloning between layers */
220         MTFace         *dm_mtface_stencil;
221
222         Image *stencil_ima;
223         float stencil_value;
224
225         /* projection painting only */
226         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
227         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
228         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
229         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
230 #ifndef PROJ_DEBUG_NOSEAMBLEED
231         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
232         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
233         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
234         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
235 #endif
236         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
237         int buckets_x;                      /* The size of the bucket grid, the grid span's screenMin/screenMax so you can paint outsize the screen or with 2 brushes at once */
238         int buckets_y;
239
240         ProjPaintImage *projImages;
241
242         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
243
244         int image_tot;              /* size of projectImages array */
245
246         float (*screenCoords)[4];   /* verts projected into floating point screen space */
247
248         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
249         float screenMax[2];
250         float screen_width;         /* Calculated from screenMin & screenMax */
251         float screen_height;
252         int winx, winy;             /* from the carea or from the projection render */
253
254         /* options for projection painting */
255         bool  do_layer_clone;
256         bool  do_layer_stencil;
257         bool  do_layer_stencil_inv;
258         bool  do_stencil_brush;
259
260         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
261         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
262         bool  do_mask_normal;           /* mask out pixels based on their normals */
263         bool  do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
264         float normal_angle;             /* what angle to mask at*/
265         float normal_angle_inner;
266         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
267
268         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
269         bool is_ortho;
270         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
271         bool is_texbrush;              /* only to avoid running  */
272         bool is_maskbrush;            /* mask brush is applied before masking */
273 #ifndef PROJ_DEBUG_NOSEAMBLEED
274         float seam_bleed_px;
275 #endif
276         /* clone vars */
277         float cloneOffset[2];
278
279         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
280         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
281         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
282         float clipsta, clipend;
283
284         /* reproject vars */
285         Image *reproject_image;
286         ImBuf *reproject_ibuf;
287
288         /* threads */
289         int thread_tot;
290         int bucketMin[2];
291         int bucketMax[2];
292         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
293
294         /* redraw */
295         bool need_redraw;
296
297         BlurKernel *blurkernel;
298
299         SpinLock *tile_lock;
300 } ProjPaintState;
301
302 typedef union pixelPointer {
303         float *f_pt;            /* float buffer */
304         unsigned int *uint_pt; /* 2 ways to access a char buffer */
305         unsigned char *ch_pt;
306 } PixelPointer;
307
308 typedef union pixelStore {
309         unsigned char ch[4];
310         unsigned int uint;
311         float f[4];
312 } PixelStore;
313
314 typedef struct ProjPixel {
315         float projCoSS[2]; /* the floating point screen projection of this pixel */
316         float worldCoSS[3];
317         /* Only used when the airbrush is disabled.
318          * Store the max mask value to avoid painting over an area with a lower opacity
319          * with an advantage that we can avoid touching the pixel at all, if the
320          * new mask value is lower then mask_accum */
321         unsigned short *mask_accum;
322
323         /* for various reasons we may want to mask out painting onto this pixel */
324         unsigned short mask;
325
326         short x_px, y_px;
327         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
328         bool *valid;
329
330         PixelPointer origColor;
331         PixelStore newColor;
332         PixelPointer pixel;
333
334         short image_index; /* if anyone wants to paint onto more than 32768 images they can bite me */
335         unsigned char bb_cell_index;
336 } ProjPixel;
337
338 typedef struct ProjPixelClone {
339         struct ProjPixel __pp;
340         PixelStore clonepx;
341 } ProjPixelClone;
342
343 /* undo tile pushing */
344 typedef struct {
345         SpinLock *lock;
346         bool masked;
347         unsigned short tile_width;
348         ImBuf **tmpibuf;
349         ProjPaintImage *pjima;
350 } TileInfo;
351
352
353 /* Finish projection painting structs */
354
355 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int face_index)
356 {
357         MFace *mf = ps->dm_mface + face_index;
358         Material *ma = ps->dm->mat[mf->mat_nr];
359         return ma->texpaintslot + ma->paint_active_slot;
360 }
361
362 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int face_index)
363 {
364         if (ps->do_stencil_brush) {
365                 return ps->stencil_ima;
366         }
367         else {
368                 MFace *mf = ps->dm_mface + face_index;
369                 Material *ma = ps->dm->mat[mf->mat_nr];
370                 TexPaintSlot *slot = ma->texpaintslot + ma->paint_active_slot;
371                 return slot ? slot->ima : NULL;
372         }
373 }
374
375
376 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int face_index)
377 {
378         MFace *mf = ps->dm_mface + face_index;
379         Material *ma = ps->dm->mat[mf->mat_nr];
380         return &ma->texpaintslot[ma->paint_clone_slot];
381 }
382
383 /* fast projection bucket array lookup, use the safe version for bound checking  */
384 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
385 {
386         /* If we were not dealing with screenspace 2D coords we could simple do...
387          * ps->bucketRect[x + (y*ps->buckets_y)] */
388
389         /* please explain?
390          * projCoSS[0] - ps->screenMin[0]   : zero origin
391          * ... / ps->screen_width           : range from 0.0 to 1.0
392          * ... * ps->buckets_x              : use as a bucket index
393          *
394          * Second multiplication does similar but for vertical offset
395          */
396         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
397                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
398 }
399
400 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
401 {
402         int bucket_index = project_bucket_offset(ps, projCoSS);
403
404         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
405                 return -1;
406         }
407         else {
408                 return bucket_index;
409         }
410 }
411
412 static float VecZDepthOrtho(const float pt[2],
413                             const float v1[3], const float v2[3], const float v3[3],
414                             float w[3])
415 {
416         barycentric_weights_v2(v1, v2, v3, pt, w);
417         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
418 }
419
420 static float VecZDepthPersp(const float pt[2],
421                             const float v1[4], const float v2[4], const float v3[4],
422                             float w[3])
423 {
424         float wtot_inv, wtot;
425         float w_tmp[3];
426
427         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
428         /* for the depth we need the weights to match what
429          * barycentric_weights_v2 would return, in this case its easiest just to
430          * undo the 4th axis division and make it unit-sum
431          *
432          * don't call barycentric_weights_v2() because our callers expect 'w'
433          * to be weighted from the perspective */
434         w_tmp[0] = w[0] * v1[3];
435         w_tmp[1] = w[1] * v2[3];
436         w_tmp[2] = w[2] * v3[3];
437
438         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
439
440         if (wtot != 0.0f) {
441                 wtot_inv = 1.0f / wtot;
442
443                 w_tmp[0] = w_tmp[0] * wtot_inv;
444                 w_tmp[1] = w_tmp[1] * wtot_inv;
445                 w_tmp[2] = w_tmp[2] * wtot_inv;
446         }
447         else /* dummy values for zero area face */
448                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
449         /* done mimicing barycentric_weights_v2() */
450
451         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
452 }
453
454
455 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
456 static int project_paint_PickFace(const ProjPaintState *ps, const float pt[2], float w[3], int *side)
457 {
458         LinkNode *node;
459         float w_tmp[3];
460         const float *v1, *v2, *v3, *v4;
461         int bucket_index;
462         int face_index;
463         int best_side = -1;
464         int best_face_index = -1;
465         float z_depth_best = FLT_MAX, z_depth;
466         MFace *mf;
467
468         bucket_index = project_bucket_offset_safe(ps, pt);
469         if (bucket_index == -1)
470                 return -1;
471
472
473
474         /* we could return 0 for 1 face buckets, as long as this function assumes
475          * that the point its testing is only every originated from an existing face */
476
477         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
478                 face_index = GET_INT_FROM_POINTER(node->link);
479                 mf = ps->dm_mface + face_index;
480
481                 v1 = ps->screenCoords[mf->v1];
482                 v2 = ps->screenCoords[mf->v2];
483                 v3 = ps->screenCoords[mf->v3];
484
485                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
486                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
487                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
488
489                         if (z_depth < z_depth_best) {
490                                 best_face_index = face_index;
491                                 best_side = 0;
492                                 z_depth_best = z_depth;
493                                 copy_v3_v3(w, w_tmp);
494                         }
495                 }
496                 else if (mf->v4) {
497                         v4 = ps->screenCoords[mf->v4];
498
499                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
500                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
501                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
502
503                                 if (z_depth < z_depth_best) {
504                                         best_face_index = face_index;
505                                         best_side = 1;
506                                         z_depth_best = z_depth;
507                                         copy_v3_v3(w, w_tmp);
508                                 }
509                         }
510                 }
511         }
512
513         *side = best_side;
514         return best_face_index; /* will be -1 or a valid face */
515 }
516
517 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
518 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
519 {
520         /* use */
521         *x = fmodf(uv[0], 1.0f);
522         *y = fmodf(uv[1], 1.0f);
523
524         if (*x < 0.0f) *x += 1.0f;
525         if (*y < 0.0f) *y += 1.0f;
526
527         *x = *x * ibuf_x - 0.5f;
528         *y = *y * ibuf_y - 0.5f;
529 }
530
531 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
532 static bool project_paint_PickColor(const ProjPaintState *ps, const float pt[2],
533                                     float *rgba_fp, unsigned char *rgba, const bool interp)
534 {
535         float w[3], uv[2];
536         int side;
537         int face_index;
538         MTFace *tf;
539         Image *ima;
540         ImBuf *ibuf;
541         int xi, yi;
542
543
544         face_index = project_paint_PickFace(ps, pt, w, &side);
545
546         if (face_index == -1)
547                 return 0;
548
549         tf = *(ps->dm_mtface + face_index);
550
551         if (side == 0) {
552                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
553         }
554         else { /* QUAD */
555                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
556         }
557
558         ima = project_paint_face_paint_image(ps, face_index);
559         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
560         if (!ibuf) return 0;
561
562         if (interp) {
563                 float x, y;
564                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
565
566                 if (ibuf->rect_float) {
567                         if (rgba_fp) {
568                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
569                         }
570                         else {
571                                 float rgba_tmp_f[4];
572                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
573                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
574                         }
575                 }
576                 else {
577                         if (rgba) {
578                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
579                         }
580                         else {
581                                 unsigned char rgba_tmp[4];
582                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
583                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
584                         }
585                 }
586         }
587         else {
588                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
589                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
590                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
591
592                 /* wrap */
593                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
594                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
595
596                 if (rgba) {
597                         if (ibuf->rect_float) {
598                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
599                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
600                         }
601                         else {
602                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
603                         }
604                 }
605
606                 if (rgba_fp) {
607                         if (ibuf->rect_float) {
608                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
609                         }
610                         else {
611                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
612                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
613                         }
614                 }
615         }
616         BKE_image_release_ibuf(ima, ibuf, NULL);
617         return 1;
618 }
619
620 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
621  * return...
622  *  0   : no occlusion
623  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
624  *  1   : occluded
625  *  2   : occluded with w[3] weights set (need to know in some cases) */
626
627 static int project_paint_occlude_ptv(const float pt[3],
628                                      const float v1[4], const float v2[4], const float v3[4],
629                                      float w[3], const bool is_ortho)
630 {
631         /* if all are behind us, return false */
632         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
633                 return 0;
634
635         /* do a 2D point in try intersection */
636         if (!isect_point_tri_v2(pt, v1, v2, v3))
637                 return 0;  /* we know there is  */
638
639
640         /* From here on we know there IS an intersection */
641         /* if ALL of the verts are infront of us then we know it intersects ? */
642         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
643                 return 1;
644         }
645         else {
646                 /* we intersect? - find the exact depth at the point of intersection */
647                 /* Is this point is occluded by another face? */
648                 if (is_ortho) {
649                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
650                 }
651                 else {
652                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
653                 }
654         }
655         return -1;
656 }
657
658
659 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
660                                           const float pt[3], const float v1[4], const float v2[4], const float v3[4],
661                                           const int side)
662 {
663         float w[3], wco[3];
664         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
665
666         if (ret <= 0)
667                 return ret;
668
669         if (ret == 1) { /* weights not calculated */
670                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
671                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
672         }
673
674         /* Test if we're in the clipped area, */
675         if (side) interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v3].co, ps->dm_mvert[mf->v4].co, w);
676         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
677
678         if (!ED_view3d_clipping_test(ps->rv3d, wco, true)) {
679                 return 1;
680         }
681
682         return -1;
683 }
684
685
686 /* Check if a screenspace location is occluded by any other faces
687  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
688  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
689 static bool project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace,
690                                           const int orig_face, const float pixelScreenCo[4])
691 {
692         MFace *mf;
693         int face_index;
694         int isect_ret;
695         float w[3]; /* not needed when clipping */
696         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
697
698         /* we could return 0 for 1 face buckets, as long as this function assumes
699          * that the point its testing is only every originated from an existing face */
700
701         for (; bucketFace; bucketFace = bucketFace->next) {
702                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
703
704                 if (orig_face != face_index) {
705                         mf = ps->dm_mface + face_index;
706                         if (do_clip)
707                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
708                         else
709                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
710
711                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
712                         if (isect_ret == 0 && mf->v4) {
713                                 if (do_clip)
714                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
715                                 else
716                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
717                         }
718                         if (isect_ret >= 1) {
719                                 /* TODO - we may want to cache the first hit,
720                                  * it is not possible to swap the face order in the list anymore */
721                                 return true;
722                         }
723                 }
724         }
725         return false;
726 }
727
728 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
729  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
730 #define ISECT_TRUE 1
731 #define ISECT_TRUE_P1 2
732 #define ISECT_TRUE_P2 3
733 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
734 {
735         float y_diff;
736
737         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
738                 *x_isect = p1[0];
739                 return ISECT_TRUE_P1;
740         }
741         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
742                 *x_isect = p2[0];
743                 return ISECT_TRUE_P2;
744         }
745
746         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
747
748         if (y_diff < 0.000001f) {
749                 *x_isect = (p1[0] + p2[0]) * 0.5f;
750                 return ISECT_TRUE;
751         }
752
753         if (p1[1] > y_level && p2[1] < y_level) {
754                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
755                 return ISECT_TRUE;
756         }
757         else if (p1[1] < y_level && p2[1] > y_level) {
758                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
759                 return ISECT_TRUE;
760         }
761         else {
762                 return 0;
763         }
764 }
765
766 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
767 {
768         float x_diff;
769
770         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
771                 *y_isect = p1[1];
772                 return ISECT_TRUE_P1;
773         }
774         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
775                 *y_isect = p2[1];
776                 return ISECT_TRUE_P2;
777         }
778
779         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
780
781         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
782                 *y_isect = (p1[0] + p2[0]) * 0.5f;
783                 return ISECT_TRUE;
784         }
785
786         if (p1[0] > x_level && p2[0] < x_level) {
787                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
788                 return ISECT_TRUE;
789         }
790         else if (p1[0] < x_level && p2[0] > x_level) {
791                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
792                 return ISECT_TRUE;
793         }
794         else {
795                 return 0;
796         }
797 }
798
799 /* simple func use for comparing UV locations to check if there are seams.
800  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
801  * tile, but do not do this for the adjacent face, it could return a false positive.
802  * This is so unlikely that Id not worry about it. */
803 #ifndef PROJ_DEBUG_NOSEAMBLEED
804 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
805 {
806         /* if the UV's are not between 0.0 and 1.0 */
807         float xa = fmodf(vec2a[0], 1.0f);
808         float ya = fmodf(vec2a[1], 1.0f);
809
810         float xb = fmodf(vec2b[0], 1.0f);
811         float yb = fmodf(vec2b[1], 1.0f);
812
813         if (xa < 0.0f) xa += 1.0f;
814         if (ya < 0.0f) ya += 1.0f;
815
816         if (xb < 0.0f) xb += 1.0f;
817         if (yb < 0.0f) yb += 1.0f;
818
819         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
820 }
821 #endif
822
823 /* set min_px and max_px to the image space bounds of the UV coords
824  * return zero if there is no area in the returned rectangle */
825 #ifndef PROJ_DEBUG_NOSEAMBLEED
826 static bool pixel_bounds_uv(
827         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
828         rcti *bounds_px,
829         const int ibuf_x, const int ibuf_y,
830         const bool is_quad
831         )
832 {
833         float min_uv[2], max_uv[2]; /* UV bounds */
834
835         INIT_MINMAX2(min_uv, max_uv);
836
837         minmax_v2v2_v2(min_uv, max_uv, uv1);
838         minmax_v2v2_v2(min_uv, max_uv, uv2);
839         minmax_v2v2_v2(min_uv, max_uv, uv3);
840         if (is_quad)
841                 minmax_v2v2_v2(min_uv, max_uv, uv4);
842
843         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
844         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
845
846         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
847         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
848
849         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
850
851         /* face uses no UV area when quantized to pixels? */
852         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
853 }
854 #endif
855
856 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
857 {
858         float min_uv[2], max_uv[2]; /* UV bounds */
859
860         if (tot == 0) {
861                 return 0;
862         }
863
864         INIT_MINMAX2(min_uv, max_uv);
865
866         while (tot--) {
867                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
868                 uv++;
869         }
870
871         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
872         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
873
874         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
875         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
876
877         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
878
879         /* face uses no UV area when quantized to pixels? */
880         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
881 }
882
883 #ifndef PROJ_DEBUG_NOSEAMBLEED
884
885 static void project_face_winding_init(const ProjPaintState *ps, const int face_index)
886 {
887         /* detect the winding of faces in uv space */
888         MTFace *tf = ps->dm_mtface[face_index];
889         float winding = cross_tri_v2(tf->uv[0], tf->uv[1], tf->uv[2]);
890
891         if (ps->dm_mface[face_index].v4)
892                 winding += cross_tri_v2(tf->uv[2], tf->uv[3], tf->uv[0]);
893
894         if (winding > 0)
895                 ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_CW;
896
897         ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_INIT;
898 }
899
900 /* This function returns 1 if this face has a seam along the 2 face-vert indices
901  * 'orig_i1_fidx' and 'orig_i2_fidx' */
902 static bool check_seam(const ProjPaintState *ps,
903                        const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
904                        int *other_face, int *orig_fidx)
905 {
906         LinkNode *node;
907         int face_index;
908         unsigned int i1, i2;
909         int i1_fidx = -1, i2_fidx = -1; /* index in face */
910         MFace *mf;
911         MTFace *tf;
912         const MFace *orig_mf = ps->dm_mface + orig_face;
913         const MTFace *orig_tf = ps->dm_mtface[orig_face];
914
915         /* vert indices from face vert order indices */
916         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
917         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
918
919         for (node = ps->vertFaces[i1]; node; node = node->next) {
920                 face_index = GET_INT_FROM_POINTER(node->link);
921
922                 if (face_index != orig_face) {
923                         mf = ps->dm_mface + face_index;
924                         /* could check if the 2 faces images match here,
925                          * but then there wouldn't be a way to return the opposite face's info */
926
927
928                         /* We need to know the order of the verts in the adjacent face
929                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
930                         i1_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i1);
931                         i2_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i2);
932
933                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
934                         if (i2_fidx != -1) {
935                                 Image *tpage = project_paint_face_paint_image(ps, face_index);
936                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
937
938                                 BLI_assert(i1_fidx != -1);
939
940                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
941                                 tf = ps->dm_mtface[face_index];
942
943                                 /* set up the other face */
944                                 *other_face = face_index;
945                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
946
947                                 /* initialize face winding if needed */
948                                 if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
949                                         project_face_winding_init(ps, face_index);
950
951                                 /* first test if they have the same image */
952                                 if ((orig_tpage == tpage) &&
953                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
954                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]))
955                                 {
956                                         /* if faces don't have the same winding in uv space,
957                                          * they are on the same side so edge is boundary */
958                                         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_CW) !=
959                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
960                                         {
961                                                 return 1;
962                                         }
963
964                                         // printf("SEAM (NONE)\n");
965                                         return 0;
966
967                                 }
968                                 else {
969                                         // printf("SEAM (UV GAP)\n");
970                                         return 1;
971                                 }
972                         }
973                 }
974         }
975         // printf("SEAM (NO FACE)\n");
976         *other_face = -1;
977         return 1;
978 }
979
980 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
981  * since the outset coords are a margin that keep an even distance from the original UV's,
982  * note that the image aspect is taken into account */
983 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
984                             const int ibuf_x, const int ibuf_y, const bool is_quad)
985 {
986         float a1, a2, a3, a4 = 0.0f;
987         float puv[4][2]; /* pixelspace uv's */
988         float no1[2], no2[2], no3[2], no4[2]; /* normals */
989         float dir1[2], dir2[2], dir3[2], dir4[2];
990         float ibuf_inv[2];
991
992         ibuf_inv[0] = 1.0f / (float)ibuf_x;
993         ibuf_inv[1] = 1.0f / (float)ibuf_y;
994
995         /* make UV's in pixel space so we can */
996         puv[0][0] = orig_uv[0][0] * ibuf_x;
997         puv[0][1] = orig_uv[0][1] * ibuf_y;
998
999         puv[1][0] = orig_uv[1][0] * ibuf_x;
1000         puv[1][1] = orig_uv[1][1] * ibuf_y;
1001
1002         puv[2][0] = orig_uv[2][0] * ibuf_x;
1003         puv[2][1] = orig_uv[2][1] * ibuf_y;
1004
1005         if (is_quad) {
1006                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1007                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1008         }
1009
1010         /* face edge directions */
1011         sub_v2_v2v2(dir1, puv[1], puv[0]);
1012         sub_v2_v2v2(dir2, puv[2], puv[1]);
1013         normalize_v2(dir1);
1014         normalize_v2(dir2);
1015
1016         if (is_quad) {
1017                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1018                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1019                 normalize_v2(dir3);
1020                 normalize_v2(dir4);
1021         }
1022         else {
1023                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1024                 normalize_v2(dir3);
1025         }
1026
1027         if (is_quad) {
1028                 a1 = shell_v2v2_mid_normalized_to_dist(dir4, dir1);
1029                 a2 = shell_v2v2_mid_normalized_to_dist(dir1, dir2);
1030                 a3 = shell_v2v2_mid_normalized_to_dist(dir2, dir3);
1031                 a4 = shell_v2v2_mid_normalized_to_dist(dir3, dir4);
1032         }
1033         else {
1034                 a1 = shell_v2v2_mid_normalized_to_dist(dir3, dir1);
1035                 a2 = shell_v2v2_mid_normalized_to_dist(dir1, dir2);
1036                 a3 = shell_v2v2_mid_normalized_to_dist(dir2, dir3);
1037         }
1038
1039         if (is_quad) {
1040                 sub_v2_v2v2(no1, dir4, dir1);
1041                 sub_v2_v2v2(no2, dir1, dir2);
1042                 sub_v2_v2v2(no3, dir2, dir3);
1043                 sub_v2_v2v2(no4, dir3, dir4);
1044                 normalize_v2(no1);
1045                 normalize_v2(no2);
1046                 normalize_v2(no3);
1047                 normalize_v2(no4);
1048                 mul_v2_fl(no1, a1 * scaler);
1049                 mul_v2_fl(no2, a2 * scaler);
1050                 mul_v2_fl(no3, a3 * scaler);
1051                 mul_v2_fl(no4, a4 * scaler);
1052                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1053                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1054                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1055                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1056                 mul_v2_v2(outset_uv[0], ibuf_inv);
1057                 mul_v2_v2(outset_uv[1], ibuf_inv);
1058                 mul_v2_v2(outset_uv[2], ibuf_inv);
1059                 mul_v2_v2(outset_uv[3], ibuf_inv);
1060         }
1061         else {
1062                 sub_v2_v2v2(no1, dir3, dir1);
1063                 sub_v2_v2v2(no2, dir1, dir2);
1064                 sub_v2_v2v2(no3, dir2, dir3);
1065                 normalize_v2(no1);
1066                 normalize_v2(no2);
1067                 normalize_v2(no3);
1068                 mul_v2_fl(no1, a1 * scaler);
1069                 mul_v2_fl(no2, a2 * scaler);
1070                 mul_v2_fl(no3, a3 * scaler);
1071                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1072                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1073                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1074
1075                 mul_v2_v2(outset_uv[0], ibuf_inv);
1076                 mul_v2_v2(outset_uv[1], ibuf_inv);
1077                 mul_v2_v2(outset_uv[2], ibuf_inv);
1078         }
1079 }
1080
1081 /*
1082  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1083  * 1<<i - where i is (0-3)
1084  *
1085  * If we're multithreadng, make sure threads are locked when this is called
1086  */
1087 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1088 {
1089         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1090         int fidx1 = is_quad ? 3 : 2;
1091         int fidx2 = 0; /* next fidx in the face (0,1,2,3) -> (1,2,3,0) or (0,1,2) -> (1,2,0) for a tri */
1092
1093         /* initialize face winding if needed */
1094         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
1095                 project_face_winding_init(ps, face_index);
1096
1097         do {
1098                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1099                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1100                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1101                                 if (other_face != -1)
1102                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1103                         }
1104                         else {
1105                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1106                                 if (other_face != -1)
1107                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1108                         }
1109                 }
1110
1111                 fidx2 = fidx1;
1112         } while (fidx1--);
1113 }
1114 #endif // PROJ_DEBUG_NOSEAMBLEED
1115
1116
1117 /* Converts a UV location to a 3D screenspace location
1118  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1119  *
1120  * This is used for finding a pixels location in screenspace for painting */
1121 static void screen_px_from_ortho(
1122         const float uv[2],
1123         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1124         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1125         float pixelScreenCo[4],
1126         float w[3])
1127 {
1128         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1129         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1130 }
1131
1132 /* same as screen_px_from_ortho except we
1133  * do perspective correction on the pixel coordinate */
1134 static void screen_px_from_persp(
1135         const float uv[2],
1136         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1137         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1138         float pixelScreenCo[4],
1139         float w[3])
1140 {
1141         float w_int[3];
1142         float wtot_inv, wtot;
1143         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1144
1145         /* re-weight from the 4th coord of each screen vert */
1146         w_int[0] = w[0] * v1co[3];
1147         w_int[1] = w[1] * v2co[3];
1148         w_int[2] = w[2] * v3co[3];
1149
1150         wtot = w_int[0] + w_int[1] + w_int[2];
1151
1152         if (wtot > 0.0f) {
1153                 wtot_inv = 1.0f / wtot;
1154                 w_int[0] *= wtot_inv;
1155                 w_int[1] *= wtot_inv;
1156                 w_int[2] *= wtot_inv;
1157         }
1158         else {
1159                 w[0] = w[1] = w[2] =
1160                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1161         }
1162         /* done re-weighting */
1163
1164         /* do interpolation based on projected weight */
1165         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1166 }
1167
1168
1169 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1170                                int side, unsigned char rgba_ub[4], float rgba_f[4])
1171 {
1172         const float *uvCo1, *uvCo2, *uvCo3;
1173         float uv_other[2], x, y;
1174
1175         uvCo1 =  (float *)tf_other->uv[0];
1176         if (side == 1) {
1177                 uvCo2 =  (float *)tf_other->uv[2];
1178                 uvCo3 =  (float *)tf_other->uv[3];
1179         }
1180         else {
1181                 uvCo2 =  (float *)tf_other->uv[1];
1182                 uvCo3 =  (float *)tf_other->uv[2];
1183         }
1184
1185         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1186
1187         /* use */
1188         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1189
1190
1191         if (ibuf_other->rect_float) { /* from float to float */
1192                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1193         }
1194         else { /* from char to float */
1195                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1196         }
1197
1198 }
1199
1200 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1201 static float project_paint_uvpixel_mask(
1202         const ProjPaintState *ps,
1203         const int face_index,
1204         const int side,
1205         const float w[3])
1206 {
1207         float mask;
1208
1209         /* Image Mask */
1210         if (ps->do_layer_stencil) {
1211                 /* another UV maps image is masking this one's */
1212                 ImBuf *ibuf_other;
1213                 Image *other_tpage = ps->stencil_ima;
1214                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1215
1216                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1217                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1218                         unsigned char rgba_ub[4];
1219                         float rgba_f[4];
1220
1221                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1222
1223                         if (ibuf_other->rect_float) { /* from float to float */
1224                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1225                         }
1226                         else { /* from char to float */
1227                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1228                         }
1229
1230                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1231
1232                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1233                                 mask = (1.0f - mask);
1234
1235                         if (mask == 0.0f) {
1236                                 return 0.0f;
1237                         }
1238                 }
1239                 else {
1240                         return 0.0f;
1241                 }
1242         }
1243         else {
1244                 mask = 1.0f;
1245         }
1246
1247         /* calculate mask */
1248         if (ps->do_mask_normal) {
1249                 MFace *mf = &ps->dm_mface[face_index];
1250                 float no[3], angle;
1251                 if (mf->flag & ME_SMOOTH) {
1252                         const short *no1, *no2, *no3;
1253                         no1 = ps->dm_mvert[mf->v1].no;
1254                         if (side == 1) {
1255                                 no2 = ps->dm_mvert[mf->v3].no;
1256                                 no3 = ps->dm_mvert[mf->v4].no;
1257                         }
1258                         else {
1259                                 no2 = ps->dm_mvert[mf->v2].no;
1260                                 no3 = ps->dm_mvert[mf->v3].no;
1261                         }
1262
1263                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1264                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1265                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1266                         normalize_v3(no);
1267                 }
1268                 else {
1269                         /* incase the */
1270 #if 1
1271                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1272                         if (mf->v4)
1273                                 normal_quad_v3(no,
1274                                                ps->dm_mvert[mf->v1].co,
1275                                                ps->dm_mvert[mf->v2].co,
1276                                                ps->dm_mvert[mf->v3].co,
1277                                                ps->dm_mvert[mf->v4].co);
1278                         else
1279                                 normal_tri_v3(no,
1280                                               ps->dm_mvert[mf->v1].co,
1281                                               ps->dm_mvert[mf->v2].co,
1282                                               ps->dm_mvert[mf->v3].co);
1283 #else
1284                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1285                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1286 #endif
1287                 }
1288
1289                 /* now we can use the normal as a mask */
1290                 if (ps->is_ortho) {
1291                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1292                 }
1293                 else {
1294                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1295                         float viewDirPersp[3];
1296                         const float *co1, *co2, *co3;
1297                         co1 = ps->dm_mvert[mf->v1].co;
1298                         if (side == 1) {
1299                                 co2 = ps->dm_mvert[mf->v3].co;
1300                                 co3 = ps->dm_mvert[mf->v4].co;
1301                         }
1302                         else {
1303                                 co2 = ps->dm_mvert[mf->v2].co;
1304                                 co3 = ps->dm_mvert[mf->v3].co;
1305                         }
1306
1307                         /* Get the direction from the viewPoint to the pixel and normalize */
1308                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1309                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1310                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1311                         normalize_v3(viewDirPersp);
1312
1313                         angle = angle_normalized_v3v3(viewDirPersp, no);
1314                 }
1315
1316                 if (angle >= ps->normal_angle) {
1317                         return 0.0f; /* outsize the normal limit*/
1318                 }
1319                 else if (angle > ps->normal_angle_inner) {
1320                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1321                 } /* otherwise no mask normal is needed, were within the limit */
1322         }
1323
1324         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1325          * so don't use it. */
1326         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1327
1328         return mask;
1329 }
1330
1331 static int project_paint_pixel_sizeof(const short tool)
1332 {
1333         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1334                 return sizeof(ProjPixelClone);
1335         }
1336         else {
1337                 return sizeof(ProjPixel);
1338         }
1339 }
1340
1341 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1342 {
1343         ProjPaintImage *pjIma = tinf->pjima;
1344         int tile_index = tx + ty * tinf->tile_width;
1345         bool generate_tile = false;
1346
1347         /* double check lock to avoid locking */
1348         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1349                 if (tinf->lock)
1350                         BLI_spin_lock(tinf->lock);
1351                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1352                         pjIma->undoRect[tile_index] = TILE_PENDING;
1353                         generate_tile = true;
1354                 }
1355                 if (tinf->lock)
1356                         BLI_spin_unlock(tinf->lock);
1357         }
1358
1359
1360         if (generate_tile) {
1361                 volatile void *undorect;
1362                 if (tinf->masked) {
1363                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true);
1364                 }
1365                 else {
1366                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, NULL, &pjIma->valid[tile_index], true);
1367                 }
1368
1369                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1370                 /* tile ready, publish */
1371                 if (tinf->lock)
1372                         BLI_spin_lock(tinf->lock);
1373                 pjIma->undoRect[tile_index] = undorect;
1374                 if (tinf->lock)
1375                         BLI_spin_unlock(tinf->lock);
1376
1377         }
1378
1379         return tile_index;
1380 }
1381
1382 /* run this function when we know a bucket's, face's pixel can be initialized,
1383  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1384 static ProjPixel *project_paint_uvpixel_init(
1385         const ProjPaintState *ps,
1386         MemArena *arena,
1387         const TileInfo *tinf,
1388         int x_px, int y_px,
1389         const float mask,
1390         const int face_index,
1391         const float pixelScreenCo[4],
1392         const float world_spaceCo[3],
1393         const int side,
1394         const float w[3])
1395 {
1396         ProjPixel *projPixel;
1397         int x_tile, y_tile;
1398         int x_round, y_round;
1399         int tile_offset;
1400         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1401         volatile int tile_index;
1402
1403         ProjPaintImage *projima = tinf->pjima;
1404         ImBuf *ibuf = projima->ibuf;
1405         /* wrap pixel location */
1406
1407         x_px = mod_i(x_px, ibuf->x);
1408         y_px = mod_i(y_px, ibuf->y);
1409
1410         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1411         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, ps->pixel_sizeof);
1412
1413         /* calculate the undo tile offset of the pixel, used to store the original
1414          * pixel color and accumulated mask if any */
1415         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1416         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1417
1418         x_round = x_tile * IMAPAINT_TILE_SIZE;
1419         y_round = y_tile * IMAPAINT_TILE_SIZE;
1420         //memset(projPixel, 0, size);
1421
1422         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1423         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1424
1425         /* other thread may be initializing the tile so wait here */
1426         while (projima->undoRect[tile_index] == TILE_PENDING)
1427                 ;
1428
1429         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1430         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1431
1432         projPixel->valid = projima->valid[tile_index];
1433
1434         if (ibuf->rect_float) {
1435                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1436                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1437                 zero_v4(projPixel->newColor.f);
1438         }
1439         else {
1440                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1441                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1442                 projPixel->newColor.uint = 0;
1443         }
1444
1445         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1446         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1447                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1448         }
1449
1450         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1451
1452         projPixel->x_px = x_px;
1453         projPixel->y_px = y_px;
1454
1455         projPixel->mask = (unsigned short)(mask * 65535);
1456         if (ps->do_masking)
1457                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1458         else
1459                 projPixel->mask_accum = NULL;
1460
1461         /* which bounding box cell are we in?, needed for undo */
1462         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1463                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1464
1465         /* done with view3d_project_float inline */
1466         if (ps->tool == PAINT_TOOL_CLONE) {
1467                 if (ps->dm_mtface_clone) {
1468                         ImBuf *ibuf_other;
1469                         Image *other_tpage = project_paint_face_clone_slot(ps, face_index)->ima;
1470                         const MTFace *tf_other = ps->dm_mtface_clone[face_index];
1471
1472                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1473                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1474
1475                                 if (ibuf->rect_float) {
1476                                         if (ibuf_other->rect_float) { /* from float to float */
1477                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1478                                         }
1479                                         else { /* from char to float */
1480                                                 unsigned char rgba_ub[4];
1481                                                 float rgba[4];
1482                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1483                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1484                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1485                                         }
1486                                 }
1487                                 else {
1488                                         if (ibuf_other->rect_float) { /* float to char */
1489                                                 float rgba[4];
1490                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1491                                                 premul_to_straight_v4(rgba);
1492                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1493                                         }
1494                                         else { /* char to char */
1495                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1496                                         }
1497                                 }
1498
1499                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1500                         }
1501                         else {
1502                                 if (ibuf->rect_float) {
1503                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1504                                 }
1505                                 else {
1506                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1507                                 }
1508                         }
1509
1510                 }
1511                 else {
1512                         float co[2];
1513                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1514
1515                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1516                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1517                         if (ibuf->rect_float) {
1518                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1519                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1520                                 }
1521                         }
1522                         else {
1523                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1524                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1525                                 }
1526                         }
1527                 }
1528         }
1529
1530 #ifdef PROJ_DEBUG_PAINT
1531         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1532         else                  projPixel->pixel.ch_pt[0] = 0;
1533 #endif
1534         /* pointer arithmetics */
1535         projPixel->image_index = projima - ps->projImages;
1536
1537         return projPixel;
1538 }
1539
1540 static bool line_clip_rect2f(
1541         rctf *rect,
1542         const float l1[2], const float l2[2],
1543         float l1_clip[2], float l2_clip[2])
1544 {
1545         /* first account for horizontal, then vertical lines */
1546         /* horiz */
1547         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1548                 /* is the line out of range on its Y axis? */
1549                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1550                         return 0;
1551                 }
1552                 /* line is out of range on its X axis */
1553                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1554                         return 0;
1555                 }
1556
1557
1558                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1559                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1560                                 copy_v2_v2(l1_clip, l1);
1561                                 copy_v2_v2(l2_clip, l2);
1562                                 return 1;
1563                         }
1564                         else {
1565                                 return 0;
1566                         }
1567                 }
1568
1569                 copy_v2_v2(l1_clip, l1);
1570                 copy_v2_v2(l2_clip, l2);
1571                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1572                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1573                 return 1;
1574         }
1575         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1576                 /* is the line out of range on its X axis? */
1577                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1578                         return 0;
1579                 }
1580
1581                 /* line is out of range on its Y axis */
1582                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1583                         return 0;
1584                 }
1585
1586                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1587                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1588                                 copy_v2_v2(l1_clip, l1);
1589                                 copy_v2_v2(l2_clip, l2);
1590                                 return 1;
1591                         }
1592                         else {
1593                                 return 0;
1594                         }
1595                 }
1596
1597                 copy_v2_v2(l1_clip, l1);
1598                 copy_v2_v2(l2_clip, l2);
1599                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1600                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1601                 return 1;
1602         }
1603         else {
1604                 float isect;
1605                 short ok1 = 0;
1606                 short ok2 = 0;
1607
1608                 /* Done with vertical lines */
1609
1610                 /* are either of the points inside the rectangle ? */
1611                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1612                         copy_v2_v2(l1_clip, l1);
1613                         ok1 = 1;
1614                 }
1615
1616                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1617                         copy_v2_v2(l2_clip, l2);
1618                         ok2 = 1;
1619                 }
1620
1621                 /* line inside rect */
1622                 if (ok1 && ok2) return 1;
1623
1624                 /* top/bottom */
1625                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1626                         if (l1[1] < l2[1]) { /* line 1 is outside */
1627                                 l1_clip[0] = isect;
1628                                 l1_clip[1] = rect->ymin;
1629                                 ok1 = 1;
1630                         }
1631                         else {
1632                                 l2_clip[0] = isect;
1633                                 l2_clip[1] = rect->ymin;
1634                                 ok2 = 2;
1635                         }
1636                 }
1637
1638                 if (ok1 && ok2) return 1;
1639
1640                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1641                         if (l1[1] > l2[1]) { /* line 1 is outside */
1642                                 l1_clip[0] = isect;
1643                                 l1_clip[1] = rect->ymax;
1644                                 ok1 = 1;
1645                         }
1646                         else {
1647                                 l2_clip[0] = isect;
1648                                 l2_clip[1] = rect->ymax;
1649                                 ok2 = 2;
1650                         }
1651                 }
1652
1653                 if (ok1 && ok2) return 1;
1654
1655                 /* left/right */
1656                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1657                         if (l1[0] < l2[0]) { /* line 1 is outside */
1658                                 l1_clip[0] = rect->xmin;
1659                                 l1_clip[1] = isect;
1660                                 ok1 = 1;
1661                         }
1662                         else {
1663                                 l2_clip[0] = rect->xmin;
1664                                 l2_clip[1] = isect;
1665                                 ok2 = 2;
1666                         }
1667                 }
1668
1669                 if (ok1 && ok2) return 1;
1670
1671                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1672                         if (l1[0] > l2[0]) { /* line 1 is outside */
1673                                 l1_clip[0] = rect->xmax;
1674                                 l1_clip[1] = isect;
1675                                 ok1 = 1;
1676                         }
1677                         else {
1678                                 l2_clip[0] = rect->xmax;
1679                                 l2_clip[1] = isect;
1680                                 ok2 = 2;
1681                         }
1682                 }
1683
1684                 if (ok1 && ok2) {
1685                         return 1;
1686                 }
1687                 else {
1688                         return 0;
1689                 }
1690         }
1691 }
1692
1693
1694
1695 /* scale the quad & tri about its center
1696  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1697  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1698 #ifndef PROJ_DEBUG_NOSEAMBLEED
1699 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1700 {
1701         float cent[3];
1702         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1703         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1704         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1705
1706         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1707         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1708         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1709         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1710
1711         mul_v3_fl(insetCos[0], inset);
1712         mul_v3_fl(insetCos[1], inset);
1713         mul_v3_fl(insetCos[2], inset);
1714         mul_v3_fl(insetCos[3], inset);
1715
1716         add_v3_v3(insetCos[0], cent);
1717         add_v3_v3(insetCos[1], cent);
1718         add_v3_v3(insetCos[2], cent);
1719         add_v3_v3(insetCos[3], cent);
1720 }
1721
1722
1723 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1724 {
1725         float cent[3];
1726         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1727         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1728         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1729
1730         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1731         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1732         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1733
1734         mul_v3_fl(insetCos[0], inset);
1735         mul_v3_fl(insetCos[1], inset);
1736         mul_v3_fl(insetCos[2], inset);
1737
1738         add_v3_v3(insetCos[0], cent);
1739         add_v3_v3(insetCos[1], cent);
1740         add_v3_v3(insetCos[2], cent);
1741 }
1742 #endif //PROJ_DEBUG_NOSEAMBLEED
1743
1744 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1745 {
1746         float x, y;
1747
1748         x = v1[0] - v2_1;
1749         y = v1[1] - v2_2;
1750         return x * x + y * y;
1751 }
1752
1753 /* note, use a squared value so we can use len_squared_v2v2
1754  * be sure that you have done a bounds check first or this may fail */
1755 /* only give bucket_bounds as an arg because we need it elsewhere */
1756 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1757 {
1758
1759         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1760          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1761          * this is even less work then an intersection test
1762          */
1763 #if 0
1764         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1765                 return 1;
1766 #endif
1767
1768         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1769             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1770         {
1771                 return 1;
1772         }
1773
1774         /* out of bounds left */
1775         if (cent[0] < bucket_bounds->xmin) {
1776                 /* lower left out of radius test */
1777                 if (cent[1] < bucket_bounds->ymin) {
1778                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1779                 }
1780                 /* top left test */
1781                 else if (cent[1] > bucket_bounds->ymax) {
1782                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1783                 }
1784         }
1785         else if (cent[0] > bucket_bounds->xmax) {
1786                 /* lower right out of radius test */
1787                 if (cent[1] < bucket_bounds->ymin) {
1788                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1789                 }
1790                 /* top right test */
1791                 else if (cent[1] > bucket_bounds->ymax) {
1792                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1793                 }
1794         }
1795
1796         return 0;
1797 }
1798
1799
1800
1801 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1802  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1803  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1804  * (viewed from the side)
1805  *
1806  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1807  * funcs that only account for points inside the triangle.
1808  * however switching back to this for ortho is always an option */
1809
1810 static void rect_to_uvspace_ortho(
1811         rctf *bucket_bounds,
1812         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1813         const float *uv1co, const float *uv2co, const float *uv3co,
1814         float bucket_bounds_uv[4][2],
1815         const int flip)
1816 {
1817         float uv[2];
1818         float w[3];
1819
1820         /* get the UV space bounding box */
1821         uv[0] = bucket_bounds->xmax;
1822         uv[1] = bucket_bounds->ymin;
1823         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1824         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1825
1826         //uv[0] = bucket_bounds->xmax; // set above
1827         uv[1] = bucket_bounds->ymax;
1828         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1829         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1830
1831         uv[0] = bucket_bounds->xmin;
1832         //uv[1] = bucket_bounds->ymax; // set above
1833         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1834         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1835
1836         //uv[0] = bucket_bounds->xmin; // set above
1837         uv[1] = bucket_bounds->ymin;
1838         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1839         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1840 }
1841
1842 /* same as above but use barycentric_weights_v2_persp */
1843 static void rect_to_uvspace_persp(
1844         rctf *bucket_bounds,
1845         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1846         const float *uv1co, const float *uv2co, const float *uv3co,
1847         float bucket_bounds_uv[4][2],
1848         const int flip
1849         )
1850 {
1851         float uv[2];
1852         float w[3];
1853
1854         /* get the UV space bounding box */
1855         uv[0] = bucket_bounds->xmax;
1856         uv[1] = bucket_bounds->ymin;
1857         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1858         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1859
1860         //uv[0] = bucket_bounds->xmax; // set above
1861         uv[1] = bucket_bounds->ymax;
1862         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1863         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1864
1865         uv[0] = bucket_bounds->xmin;
1866         //uv[1] = bucket_bounds->ymax; // set above
1867         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1868         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1869
1870         //uv[0] = bucket_bounds->xmin; // set above
1871         uv[1] = bucket_bounds->ymin;
1872         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1873         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1874 }
1875
1876 /* This works as we need it to but we can save a few steps and not use it */
1877
1878 #if 0
1879 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1880 {
1881         float v1[2], v2[2];
1882
1883         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1884         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1885
1886         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1887 }
1888 #endif
1889
1890 #define ISECT_1 (1)
1891 #define ISECT_2 (1 << 1)
1892 #define ISECT_3 (1 << 2)
1893 #define ISECT_4 (1 << 3)
1894 #define ISECT_ALL3 ((1 << 3) - 1)
1895 #define ISECT_ALL4 ((1 << 4) - 1)
1896
1897 /* limit must be a fraction over 1.0f */
1898 static bool IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1899 {
1900         return ((area_tri_v2(pt, v1, v2) +
1901                  area_tri_v2(pt, v2, v3) +
1902                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
1903 }
1904
1905 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1906  * so we have the clipped UV's to do pixel intersection tests with
1907  * */
1908 static int float_z_sort_flip(const void *p1, const void *p2)
1909 {
1910         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1911 }
1912
1913 static int float_z_sort(const void *p1, const void *p2)
1914 {
1915         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1916 }
1917
1918 static void project_bucket_clip_face(
1919         const bool is_ortho,
1920         rctf *bucket_bounds,
1921         float *v1coSS, float *v2coSS, float *v3coSS,
1922         const float *uv1co, const float *uv2co, const float *uv3co,
1923         float bucket_bounds_uv[8][2],
1924         int *tot)
1925 {
1926         int inside_bucket_flag = 0;
1927         int inside_face_flag = 0;
1928         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1929
1930         float bucket_bounds_ss[4][2];
1931
1932         /* get the UV space bounding box */
1933         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1934         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1935         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1936
1937         if (inside_bucket_flag == ISECT_ALL3) {
1938                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1939                 if (flip) { /* facing the back? */
1940                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1941                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1942                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1943                 }
1944                 else {
1945                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1946                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1947                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1948                 }
1949
1950                 *tot = 3;
1951                 return;
1952         }
1953
1954         /* get the UV space bounding box */
1955         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
1956         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
1957         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
1958         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
1959
1960         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
1961         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
1962         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
1963
1964         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
1965         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
1966         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
1967
1968         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
1969         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
1970         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
1971
1972         if (inside_face_flag == ISECT_ALL4) {
1973                 /* bucket is totally inside the screenspace face, we can safely use weights */
1974
1975                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1976                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1977
1978                 *tot = 4;
1979                 return;
1980         }
1981         else {
1982                 /* The Complicated Case!
1983                  *
1984                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
1985                  *
1986                  * we need to make a convex polyline from the intersection between the screenspace face
1987                  * and the bucket bounds.
1988                  *
1989                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
1990                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
1991                  * do a correct clipping on both shapes. */
1992
1993
1994                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
1995
1996
1997
1998                 /* Maximum possible 6 intersections when using a rectangle and triangle */
1999                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2000                 float v1_clipSS[2], v2_clipSS[2];
2001                 float w[3];
2002
2003                 /* calc center */
2004                 float cent[2] = {0.0f, 0.0f};
2005                 /*float up[2] = {0.0f, 1.0f};*/
2006                 int i;
2007                 short doubles;
2008
2009                 (*tot) = 0;
2010
2011                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2012                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2013                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2014                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2015
2016                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2017                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2018                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2019
2020                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2021                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2022                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2023                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2024                         }
2025                 }
2026
2027                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2028                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2029                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2030                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2031                         }
2032                 }
2033
2034                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2035                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2036                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2037                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2038                         }
2039                 }
2040
2041
2042                 if ((*tot) < 3) { /* no intersections to speak of */
2043                         *tot = 0;
2044                         return;
2045                 }
2046
2047                 /* now we have all points we need, collect their angles and sort them clockwise */
2048
2049                 for (i = 0; i < (*tot); i++) {
2050                         cent[0] += isectVCosSS[i][0];
2051                         cent[1] += isectVCosSS[i][1];
2052                 }
2053                 cent[0] = cent[0] / (float)(*tot);
2054                 cent[1] = cent[1] / (float)(*tot);
2055
2056
2057
2058                 /* Collect angles for every point around the center point */
2059
2060
2061 #if 0   /* uses a few more cycles then the above loop */
2062                 for (i = 0; i < (*tot); i++) {
2063                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2064                 }
2065 #endif
2066
2067                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2068                 v1_clipSS[1] = cent[1] + 1.0f;
2069
2070                 for (i = 0; i < (*tot); i++) {
2071                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2072                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2073                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0], v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2074                 }
2075
2076                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2077                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2078
2079                 /* remove doubles */
2080                 /* first/last check */
2081                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_PIXEL_TOLERANCE &&
2082                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_PIXEL_TOLERANCE)
2083                 {
2084                         (*tot)--;
2085                 }
2086
2087                 /* its possible there is only a few left after remove doubles */
2088                 if ((*tot) < 3) {
2089                         // printf("removed too many doubles A\n");
2090                         *tot = 0;
2091                         return;
2092                 }
2093
2094                 doubles = true;
2095                 while (doubles == true) {
2096                         doubles = false;
2097                         for (i = 1; i < (*tot); i++) {
2098                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2099                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2100                                 {
2101                                         int j;
2102                                         for (j = i + 1; j < (*tot); j++) {
2103                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
2104                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
2105                                         }
2106                                         doubles = true; /* keep looking for more doubles */
2107                                         (*tot)--;
2108                                 }
2109                         }
2110                 }
2111
2112                 /* its possible there is only a few left after remove doubles */
2113                 if ((*tot) < 3) {
2114                         // printf("removed too many doubles B\n");
2115                         *tot = 0;
2116                         return;
2117                 }
2118
2119
2120                 if (is_ortho) {
2121                         for (i = 0; i < (*tot); i++) {
2122                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2123                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2124                         }
2125                 }
2126                 else {
2127                         for (i = 0; i < (*tot); i++) {
2128                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2129                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2130                         }
2131                 }
2132         }
2133
2134 #ifdef PROJ_DEBUG_PRINT_CLIP
2135         /* include this at the bottom of the above function to debug the output */
2136
2137         {
2138                 /* If there are ever any problems, */
2139                 float test_uv[4][2];
2140                 int i;
2141                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2142                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2143                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ", test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],    test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2144
2145                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2146
2147                 printf("[");
2148                 for (i = 0; i < (*tot); i++) {
2149                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2150                 }
2151                 printf("]),\\\n");
2152         }
2153 #endif
2154 }
2155
2156 /*
2157  * # This script creates faces in a blender scene from printed data above.
2158  *
2159  * project_ls = [
2160  * ...(output from above block)...
2161  * ]
2162  *
2163  * from Blender import Scene, Mesh, Window, sys, Mathutils
2164  *
2165  * import bpy
2166  *
2167  * V = Mathutils.Vector
2168  *
2169  * def main():
2170  *     sce = bpy.data.scenes.active
2171  *
2172  *     for item in project_ls:
2173  *         bb = item[0]
2174  *         uv = item[1]
2175  *         poly = item[2]
2176  *
2177  *         me = bpy.data.meshes.new()
2178  *         ob = sce.objects.new(me)
2179  *
2180  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2181  *         me.faces.extend([(0,1,2,3),])
2182  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2183  *         me.faces.extend([(4,5,6),])
2184  *
2185  *         vs = [V(p).xyz for p in poly]
2186  *         print len(vs)
2187  *         l = len(me.verts)
2188  *         me.verts.extend(vs)
2189  *
2190  *         i = l
2191  *         while i < len(me.verts):
2192  *             ii = i + 1
2193  *             if ii == len(me.verts):
2194  *                 ii = l
2195  *             me.edges.extend([i, ii])
2196  *             i += 1
2197  *
2198  * if __name__ == '__main__':
2199  *     main()
2200  */
2201
2202
2203 #undef ISECT_1
2204 #undef ISECT_2
2205 #undef ISECT_3
2206 #undef ISECT_4
2207 #undef ISECT_ALL3
2208 #undef ISECT_ALL4
2209
2210
2211 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2212  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2213 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2214 {
2215         int i;
2216         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2217                 return 0;
2218
2219         for (i = 1; i < tot; i++) {
2220                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2221                         return 0;
2222
2223         }
2224
2225         return 1;
2226 }
2227 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2228 {
2229         int i;
2230         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2231
2232         for (i = 1; i < tot; i++) {
2233                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2234                         return 0;
2235
2236         }
2237
2238         return 1;
2239 }
2240
2241 /* One of the most important function for projection painting, since it selects the pixels to be added into each bucket.
2242  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2243 static void project_paint_face_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, const int face_index, const int image_index, rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf, const short clamp_u, const short clamp_v)
2244 {
2245         /* Projection vars, to get the 3D locations into screen space  */
2246         MemArena *arena = ps->arena_mt[thread_index];
2247         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2248         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2249         bool threaded = (ps->thread_tot > 1);
2250
2251         TileInfo tinf = {
2252                 ps->tile_lock,
2253                 ps->do_masking,
2254                 IMAPAINT_TILE_NUMBER(ibuf->x),
2255                 tmpibuf,
2256                 ps->projImages + image_index
2257         };
2258
2259         const MFace *mf = ps->dm_mface + face_index;
2260         const MTFace *tf = ps->dm_mtface[face_index];
2261
2262         /* UV/pixel seeking data */
2263         int x; /* Image X-Pixel */
2264         int y; /* Image Y-Pixel */
2265         float mask;
2266         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2267
2268         int side;
2269         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2270
2271         float *vCo[4]; /* vertex screenspace coords */
2272
2273         float w[3], wco[3];
2274
2275         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2276         float pixelScreenCo[4];
2277         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2278
2279         rcti bounds_px; /* ispace bounds */
2280         /* vars for getting uvspace bounds */
2281
2282         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2283         float xhalfpx, yhalfpx;
2284         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2285
2286         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2287
2288         int i1, i2, i3;
2289
2290         float uv_clip[8][2];
2291         int uv_clip_tot;
2292         const bool is_ortho = ps->is_ortho;
2293         const bool do_backfacecull = ps->do_backfacecull;
2294         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2295
2296         vCo[0] = ps->dm_mvert[mf->v1].co;
2297         vCo[1] = ps->dm_mvert[mf->v2].co;
2298         vCo[2] = ps->dm_mvert[mf->v3].co;
2299
2300
2301         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2302          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2303          * problems when wrapping negative coords */
2304         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2305         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2306
2307         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2308          * Needed to add this offset since UV coords are often quads aligned to pixels.
2309          * In this case pixels can be exactly between 2 triangles causing nasty
2310          * artifacts.
2311          *
2312          * This workaround can be removed and painting will still work on most cases
2313          * but since the first thing most people try is painting onto a quad- better make it work.
2314          */
2315
2316         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2317         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2318
2319         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2320         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2321
2322         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2323         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2324
2325         if (mf->v4) {
2326                 vCo[3] = ps->dm_mvert[mf->v4].co;
2327
2328                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2329                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2330                 side = 1;
2331         }
2332         else {
2333                 side = 0;
2334         }
2335
2336         do {
2337                 if (side == 1) {
2338                         i1 = 0; i2 = 2; i3 = 3;
2339                 }
2340                 else {
2341                         i1 = 0; i2 = 1; i3 = 2;
2342                 }
2343
2344                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2345                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2346                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2347
2348                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2349                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2350                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2351
2352                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2353                 project_bucket_clip_face(
2354                         is_ortho, bucket_bounds,
2355                         v1coSS, v2coSS, v3coSS,
2356                         uv1co, uv2co, uv3co,
2357                         uv_clip, &uv_clip_tot
2358                         );
2359
2360                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2361 #if 0
2362                 if (uv_clip_tot > 6) {
2363                         printf("this should never happen! %d\n", uv_clip_tot);
2364                 }
2365 #endif
2366
2367                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2368
2369                         if (clamp_u) {
2370                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2371                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2372                         }
2373
2374                         if (clamp_v) {
2375                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2376                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2377                         }
2378
2379                         /*
2380                         project_paint_undo_tiles_init(&bounds_px, ps->projImages + image_index, tmpibuf,
2381                                                       tile_width, threaded, ps->do_masking);
2382                         */
2383                         /* clip face and */
2384
2385                         has_isect = 0;
2386                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2387                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2388                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2389
2390                                 has_x_isect = 0;
2391                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2392                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2393                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2394
2395                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2396                                          * could check the poly direction but better to do this */
2397                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2398                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2399                                         {
2400
2401                                                 has_x_isect = has_isect = 1;
2402
2403                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2404                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2405
2406                                                 /* a pity we need to get the worldspace pixel location here */
2407                                                 if (do_clip || do_3d_mapping) {
2408                                                         interp_v3_v3v3v3(wco, ps->dm_mvert[(*(&mf->v1 + i1))].co, ps->dm_mvert[(*(&mf->v1 + i2))].co, ps->dm_mvert[(*(&mf->v1 + i3))].co, w);
2409                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2410                                                                 continue; /* Watch out that no code below this needs to run */
2411                                                         }
2412                                                 }
2413
2414                                                 /* Is this UV visible from the view? - raytrace */
2415                                                 /* project_paint_PickFace is less complex, use for testing */
2416                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2417                                                 if ((ps->do_occlude == false) ||
2418                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2419                                                 {
2420                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2421
2422                                                         if (mask > 0.0f) {
2423                                                                 BLI_linklist_prepend_arena(
2424                                                                         bucketPixelNodes,
2425                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, face_index,
2426                                                                                                    pixelScreenCo, wco, side, w),
2427                                                                         arena
2428                                                                         );
2429                                                         }
2430                                                 }
2431
2432                                         }
2433 //#if 0
2434                                         else if (has_x_isect) {
2435                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2436                                                 break;
2437                                         }
2438 //#endif
2439                                 }
2440
2441
2442 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2443                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2444                                 if (has_x_isect == 0 && has_isect) {
2445                                         break;
2446                                 }
2447 #endif
2448                         }
2449                 }
2450         } while (side--);
2451
2452
2453
2454 #ifndef PROJ_DEBUG_NOSEAMBLEED
2455         if (ps->seam_bleed_px > 0.0f) {
2456                 int face_seam_flag;
2457
2458                 if (threaded)
2459                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2460
2461                 face_seam_flag = ps->faceSeamFlags[face_index];
2462
2463                 /* are any of our edges un-initialized? */
2464                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2465                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2466                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2467                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2468                 {
2469                         project_face_seams_init(ps, face_index, mf->v4);
2470                         face_seam_flag = ps->faceSeamFlags[face_index];
2471                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2472                 }
2473
2474                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2475
2476                         if (threaded)
2477                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2478
2479                 }
2480                 else {
2481                         /* we have a seam - deal with it! */
2482
2483                         /* Now create new UV's for the seam face */
2484                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2485                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2486
2487                         float *vCoSS[4]; /* vertex screenspace coords */
2488
2489                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2490                         float edge_verts_inset_clip[2][3];
2491                         int fidx1, fidx2; /* face edge pairs - loop throuh these ((0,1), (1,2), (2,3), (3,0)) or ((0,1), (1,2), (2,0)) for a tri */
2492
2493                         float seam_subsection[4][2];
2494                         float fac1, fac2, ftot;
2495
2496
2497                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2498                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4 != 0);
2499
2500                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2501                         if (threaded)
2502                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2503
2504                         vCoSS[0] = ps->screenCoords[mf->v1];
2505                         vCoSS[1] = ps->screenCoords[mf->v2];
2506                         vCoSS[2] = ps->screenCoords[mf->v3];
2507                         if (mf->v4)
2508                                 vCoSS[3] = ps->screenCoords[mf->v4];
2509
2510                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2511                         if (is_ortho) {
2512                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2513                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2514                         }
2515                         else {
2516                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2517                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2518                         }
2519
2520                         side = 0; /* for triangles this wont need to change */
2521
2522                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2523                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2524                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2525
2526                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2527                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2528                                 {
2529
2530                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2531
2532                                         if (ftot > 0.0f) { /* avoid div by zero */
2533                                                 if (mf->v4) {
2534                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2535                                                         else side = 0;
2536                                                 }
2537
2538                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2539                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2540
2541                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2542                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2543
2544                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2545                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2546
2547                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2548                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2549                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2550                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2551
2552
2553                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, true)) {
2554                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2555
2556                                                         has_isect = 0;
2557                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2558                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2559                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2560
2561                                                                 has_x_isect = 0;
2562                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2563                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2564                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2565
2566                                                                         /* test we're inside uvspace bucket and triangle bounds */
2567                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2568                                                                                 float fac;
2569
2570                                                                                 /* We need to find the closest point along the face edge,
2571                                                                                  * getting the screen_px_from_*** wont work because our actual location
2572                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2573                                                                                  * our location on the side of the face's UV */
2574 #if 0
2575                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2576                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2577 #endif
2578
2579                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2580                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2581
2582                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2583                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2584                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2585                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2586
2587                                                                                 if (!is_ortho) {
2588                                                                                         pixelScreenCo[3] = 1.0f;
2589                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2590                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2591                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2592                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2593                                                                                 }
2594
2595                                                                                 if ((ps->do_occlude == false) ||
2596                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2597                                                                                 {
2598                                                                                         /* Only bother calculating the weights if we intersect */
2599                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2600 #if 1
2601                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2602                                                                                                 float uv_close[2];
2603                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2604                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2605                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2606
2607                                                                                                 if (side) {
2608                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2609                                                                                                 }
2610                                                                                                 else {
2611                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2612                                                                                                 }
2613 #else                                                                                   /* this is buggy with quads, don't use for now */
2614
2615                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2616                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2617
2618                                                                                                 w[0] = w[1] = w[2] = 0.0;
2619                                                                                                 if (side) {
2620                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2621                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2622                                                                                                 }
2623                                                                                                 else {
2624                                                                                                         w[fidx1] = 1.0f - uv_fac;
2625                                                                                                         w[fidx2] = uv_fac;
2626                                                                                                 }
2627 #endif
2628                                                                                         }
2629
2630                                                                                         /* a pity we need to get the worldspace pixel location here */
2631                                                                                         if (do_clip || do_3d_mapping) {
2632                                                                                                 if (side) interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v3].co, ps->dm_mvert[mf->v4].co, w);
2633                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2634
2635                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2636                                                                                                         continue; /* Watch out that no code below this needs to run */
2637                                                                                                 }
2638                                                                                         }
2639
2640                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2641
2642                                                                                         if (mask > 0.0f) {
2643                                                                                                 BLI_linklist_prepend_arena(
2644                                                                                                         bucketPixelNodes,
2645                                                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, face_index,
2646                                                                                                         pixelScreenCo, wco, side, w),
2647                                                                                                         arena
2648                                                                                                         );
2649                                                                                         }
2650
2651                                                                                 }
2652                                                                         }
2653                                                                         else if (has_x_isect) {
2654                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2655                                                                                 break;
2656                                                                         }
2657                                                                 }
2658
2659 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2660                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2661                                                                 if (has_x_isect == 0 && has_isect) {
2662                                                                         break;
2663                                                                 }
2664 #endif
2665                                                         }
2666                                                 }
2667                                         }
2668                                 }
2669                         }
2670                 }
2671         }
2672 #endif // PROJ_DEBUG_NOSEAMBLEED
2673 }
2674
2675
2676 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2677 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2678 {
2679         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2680         /* XXX: the offset of 0.5 is always truncated to zero and the offset of 1.5f is always truncated to 1, is this really correct?? - jwilkins */
2681         bucketMin[0] = (int)((int)(((float)(min[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 0.5f); /* these offsets of 0.5 and 1.5 seem odd but they are correct */
2682         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2683
2684         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2685         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2686
2687         /* in case the rect is outside the mesh 2d bounds */
2688         CLAMP(bucketMin[0], 0, ps->buckets_x);
2689         CLAMP(bucketMin[1], 0, ps->buckets_y);
2690
2691         CLAMP(bucketMax[0], 0, ps->buckets_x);
2692         CLAMP(bucketMax[1], 0, ps->buckets_y);
2693 }
2694
2695 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2696 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2697 {
2698         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2699         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2700
2701         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2702         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2703 }
2704
2705 /* Fill this bucket with pixels from the faces that intersect it.
2706  *
2707  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2708 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2709 {
2710         LinkNode *node;
2711         int face_index, image_index = 0;
2712         ImBuf *ibuf = NULL;
2713         Image *tpage_last = NULL, *tpage;
2714         Image *ima = NULL;
2715         ImBuf *tmpibuf = NULL;
2716
2717         if (ps->image_tot == 1) {
2718                 /* Simple loop, no context switching */
2719                 ibuf = ps->projImages[0].ibuf;
2720                 ima = ps->projImages[0].ima;
2721
2722                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2723                         project_paint_face_init(ps, thread_index, bucket_index, GET_INT_FROM_POINTER(node->link), 0, bucket_bounds, ibuf, &tmpibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2724                 }
2725         }
2726         else {
2727
2728                 /* More complicated loop, switch between images */
2729                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2730                         face_index = GET_INT_FROM_POINTER(node->link);
2731
2732                         /* Image context switching */
2733                         tpage = project_paint_face_paint_image(ps, face_index);
2734                         if (tpage_last != tpage) {
2735                                 tpage_last = tpage;
2736
2737                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2738                                         if (ps->projImages[image_index].ima == tpage_last) {
2739                                                 ibuf = ps->projImages[image_index].ibuf;
2740                                                 ima = ps->projImages[image_index].ima;
2741                                                 break;
2742                                         }
2743                                 }
2744                         }
2745                         /* context switching done */
2746
2747                         project_paint_face_init(ps, thread_index, bucket_index, face_index, image_index, bucket_bounds, ibuf, &tmpibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2748                 }
2749         }
2750
2751         if (tmpibuf)
2752                 IMB_freeImBuf(tmpibuf);
2753
2754         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2755 }
2756
2757
2758 /* We want to know if a bucket and a face overlap in screen-space
2759  *
2760  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2761  * calculated when it might not be needed later, (at the moment at least)
2762  * obviously it shouldn't have bugs though */
2763
2764 static bool project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2765 {
2766         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2767         rctf bucket_bounds;
2768         float p1[2], p2[2], p3[2], p4[2];
2769         const float *v, *v1, *v2, *v3, *v4 = NULL;
2770         int fidx;
2771
2772         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2773
2774         /* Is one of the faces verts in the bucket bounds? */
2775
2776         fidx = mf->v4 ? 3 : 2;
2777         do {
2778                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2779                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2780                         return 1;
2781                 }
2782         } while (fidx--);
2783
2784         v1 = ps->screenCoords[mf->v1];
2785         v2 = ps->screenCoords[mf->v2];
2786         v3 = ps->screenCoords[mf->v3];
2787         if (mf->v4) {
2788                 v4 = ps->screenCoords[mf->v4];
2789         }
2790
2791         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2792         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2793         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2794         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2795
2796         if (mf->v4) {
2797                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2798                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2799                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2800                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2801
2802                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2803                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2804                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2805                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2806                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2807                 {
2808                         return 1;
2809                 }
2810         }
2811         else {
2812                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2813                     isect_point_tri_v2(p2, v1, v2, v3) ||
2814                     isect_point_tri_v2(p3, v1, v2, v3) ||
2815                     isect_point_tri_v2(p4, v1, v2, v3) ||
2816                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2817                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2818                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2819                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2820                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3)))
2821                 {
2822                         return 1;
2823                 }
2824         }
2825
2826         return 0;
2827 }
2828
2829 /* Add faces to the bucket but don't initialize its pixels
2830  * TODO - when painting occluded, sort the faces on their min-Z and only add faces that faces that are not occluded */
2831 static void project_paint_delayed_face_init(ProjPaintState *ps, const MFace *mf, const int face_index)
2832 {
2833         float min[2], max[2], *vCoSS;
2834         int bucketMin[2], bucketMax[2]; /* for  ps->bucketRect indexing */
2835         int fidx, bucket_x, bucket_y;
2836         int has_x_isect = -1, has_isect = 0; /* for early loop exit */
2837         MemArena *arena = ps->arena_mt[0]; /* just use the first thread arena since threading has not started yet */
2838
2839         INIT_MINMAX2(min, max);
2840
2841         fidx = mf->v4 ? 3 : 2;
2842         do {
2843                 vCoSS = ps->screenCoords[*(&mf->v1 + fidx)];
2844                 minmax_v2v2_v2(min, max, vCoSS);
2845         } while (fidx--);
2846
2847         project_paint_bucket_bounds(ps, min, max, bucketMin, bucketMax);
2848
2849         for (bucket_y = bucketMin[1]; bucket_y < bucketMax[1]; bucket_y++) {
2850                 has_x_isect = 0;
2851                 for (bucket_x = bucketMin[0]; bucket_x < bucketMax[0]; bucket_x++) {
2852                         if (project_bucket_face_isect(ps, bucket_x, bucket_y, mf)) {
2853                                 int bucket_index = bucket_x + (bucket_y * ps->buckets_x);
2854                                 BLI_linklist_prepend_arena(
2855                                         &ps->bucketFaces[bucket_index],
2856                                         SET_INT_IN_POINTER(face_index), /* cast to a pointer to shut up the compiler */
2857                                         arena
2858                                         );
2859
2860                                 has_x_isect = has_isect = 1;
2861                         }
2862                         else if (has_x_isect) {
2863                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2864                                 break;
2865                         }
2866                 }
2867
2868                 /* no intersection for this entire row, after some intersection above means we can quit now */
2869                 if (has_x_isect == 0 && has_isect) {
2870                         break;
2871                 }
2872         }
2873
2874 #ifndef PROJ_DEBUG_NOSEAMBLEED
2875         if (ps->seam_bleed_px > 0.0f) {
2876                 if (!mf->v4) {
2877                         ps->faceSeamFlags[face_index] |= PROJ_FACE_NOSEAM4; /* so this wont show up as an untagged edge */
2878                 }
2879                 **ps->faceSeamUVs[face_index] = FLT_MAX; /* set as uninitialized */